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Show 1891.] TADPOLES OF THE EUROPEAN BATRACHIANS. 61 1 acutely pointed, attenuate or mucronate at the end ; upper crest very convex and extending far forwards on the back, almost to between the eyes ; lower crest as much developed as the upper, and extending on to the belly considerably beyond the anus; the depth of the muscular portion, at its base, one third or rather less than one third the greatest total depth. Beak broadly edged with black. Lips bordered with papillae, which are absent in the middle'of the upper border \ and usually form two rows on the lower lip. Series of labial teeth |, all except the first lower occupying nearly the whole width of the lip ; the second upper is narrowly interrupted in the middle, and so is sometimes the third lower; the first lower series only one third to half as long as the second. The lines of muciferous crypts can usually be traced without much difficulty : a hoop-shaped one on each side of the head, passing above the nostril and bordering the eye above and below, both ends nearly meeting close to the upper lip, and another along each side of the body to the middle of the muscular portion of the tail. Olive above, with golden gloss; sides with golden spots ; belly white, with pearl-coloured or golden spots ; muscular part of tail yellowish, with or without blackish dots and frequently with a median black line at its base ; caudal crests whitish, immaculate or more or less profusely dotted and spotted with grey or blackish. Total length of the largest specimen from Brittany 49 millim.: body 16, width of body 12; tail 33, depth of tail 15. The Southern form, var. meridionalis, Boettger, regarded by some authors as a distinct species (H. perezi, Bosca, H. barytonus, Heron Royer), differs in its tadpole state, to judge by several specimens from Nice (which I owe to m y friend Dr. de Bedriaga), in having the second series of upper labial teeth more broadly interrupted in the middle, and in having the muscular part of the tail bordered above and below by a black line ; these two black lines together with a third running along the middle of the tail, which is immaculate or but scantily spotted, give it a peculiar appearance. The tadpole of the common Tree-Frog has been exquisitely figured by Rosel (Hist. Ran. pi. x., 1758). Far inferior figures are to be found in the works of Lataste (Actes Soc. Linn. Bord. xxx. 1876, pi. x. figs. 4-6) and Lessona (Atti Ace. Lincei, 3, i. 1877, pi. iii. fig. 18). The best descriptions are by Lataste (I. c. p. 219), Heron Royer and Van Bambeke (Arch, de Biol. ix. 1889, p. 245, pi. xv. fig. 1), and Bedriaga (Bull. Soc. Nat. Moscou, 1889, p. 476). Hyla arborea inhabits nearly the whole of the temperate parts of the Palsearctic Region, but is absent from the British Isles. The eggs are deposited in the end of April or beginning of May, and the young are ready to leave the water from the middle of July to the end of August. A case of hibernation in the larval state has been recorded by Lessona (Atti Ace. Torin. xii. 1877, p. 322). 1 I have never seen an uninterrupted series of papillae on the upper lip, as figured by Heron Royer and Van Bambeke. |